Grating for running boards



March 8, 1960 A. c. TUTTLE 2,927,514

GRATING FOR RUNNING BOARDS Filed March 26, 1956 //v VEN roR United States Patent GRATING FOR RUNNING BOARDS Alfred Claude Tuttle, Montreal, Quebec, Canada Application March 26, 1956, Serial No. 574,000

3 Claims. (Cl. 94-30) This invention relates to improvements in gratings and particularly to gratings used in running boards, catwalks and the like where strength and rigidity are required to withstand heavy loading and rough usage.

The invention consists essentially in the production of an open-work grating from a one-piece sheet of metal by slitting and bending along predetermined lines to give the desired openings and depth of grating to suit particular requirements and having a uniformly level tread surface. The tread surface resulting from the slitted and folded sheet of metal can have either smooth edges or serrated edges depending upon the ultimate use of the grating.

The slit and bent one-piece construction results in the tread surface being formed of a multiplicity of edges of the metal or folded portions producing tread edges thereby giving maximum wearing qualities and friction surface with the result that lightweight metals such as aluminum can be used thereby greatly reducing the total weight. of the grating and its cost per lb. of weight.

The object of the invention is therefore to provide a light weight grating of maximum strength from a onepiece sheet metal.

A further object of the invention is to provide a grating which can be formed into any desired shape of edge formed openings of any desired depth.

A further object of the invention is to provide a grating of one-piece construction which requires no fastening by rivets, bolts or welding except securing to an edge binding or such like support structure.

A further object of the invention is to provide a onepiece grating structure whose openings are formed of smooth vertical surfaces to allow unhindered passage downwards for snow, mud and fairly large aggregate of sand, rock or stone and thereby prevent bridging effect of these elements which would tend to close the formed apertures.

These and other objects of the invention will be ap parent from the following specification and the drawings forming a part thereof, in which Fig. 1 is a partial length of sheet metal showing a method of slitting and bending the sheet to produce a grating in which the tread edges form continuous rigid lines lengthwise and across the grating for maximum strength in all directions.

Fig. 2 is a view of the sheet illustrated in Fig. 1 after it is slit and bent and partly folded in a direction transversely of the lengthwise bends.

Fig. 3 shows the sheet of Figs. 1 and 2 fully bent to form the rigid lengthwise tread edges and showing an intermediate lengthwise tread pulled in the direction of the arrow.

Fig. 4 is a partial detail of a completed grating formed from the'sheet shown in Fig. l.

keferring tothe drawings, the sheet 40 can be of any suitable metal but preferably of lightweight metal such asaluminum. The sheet can be of any width or length,

2,927,514 Patented Mar. 8, 1959 the limit of size being controlled by the size of the equipment necessary to slit, punch and form the sheet.

The sheet 40 is first marked off by either direct marking, but preferably by template.

In order to meet certain specifications requiring a grating to have maximum strength lengthwise and transversely across the grating, which specifications can best be met by a grating having tread edges formed of continuous lines lengthwise and transversely across the grating, the method of slitting and bending the sheet is illustrated in Figures 1 and 2 of the drawings. In this method the sheet 40 is slit along the heavy marked lines 41.' Each slit formed along the lines 41 comprises two parallel sections 41a and 41b running longitudinally of the sheet and spaced apart from each other and offset longitudinally from each other, the ends of the slit sections 41a and 40b adjacent each other being joined by a transverse slit section 41C. A portion of the slit sections 41a and 41b in each longitudinal row of slits overlap the oppositely disposed section of the next adjacent slit 41 for approximately half the length of the slit sections 41a and 41b as shown in Figure l. The slits 41 in one longitudinal line are reversed in relation to the slits 41 in the next adjacent longitudinal line so that, referring to the two lines of slits shown in Figure l, the slit sections 41a in both lines lie parallel with and directly opposite each other while the slit sections 41b are spaced apart from each other and separated by the next intervening slit sections 41a. The sheet 40 is also slit in a longitudinal direction at the ends of the sheet at 42 and 43 to complete the pattern of slitting to the ends of the sheet.

After the sheet has been slit as above described, the sheet is then bent in a lengthwise direction along the lines 44 coincident with the longitudinal lines of the slit sections 41a and 41b and along the lines 45 midway between the lines of bending 44. The bends along the lines 44 and 45 are alternatively made in a reverse direction so that the sheet 40 will take a corrugated form through the stage shown in Figure 2 to the stage shown in Figure 4.

In forming the reverse bends of the sheet 40 reference is made to Figure l. The sheet is bent downwards along the top line 45 so that the line 45 forms the crest of the corrugations 50 while sheet is bent upwards along the second line 45 so that this second line 45 forms the depth of the corrugation 51 as the sheet is bent into and through the form shown in Figure 2. Each succeeding line 45 of the sheet is bent in a reverse direction from the adjacent line 45.

Secondary bends are now formed in the sheet 40. These secondary bends are formed transversely of the bends along the lines 44 and 45 and are along the lines 46 between the lentghwise sections of slits 41a and 41b. Each adjacent pair of bends along the lines 46 are formed in a reverse direction to each other to form the panels 47, 48 and 49 with the panels 48 forming a web member between the adjacent corrugations 50 and 51 of the sheet as shown in Figure 2 when the sheet is partly bent longitudinally and transversely as above described.

After the sheet 40 is slit and bent so that the lengthwise corrugations 50 and 51 are completely closed vertically to form the longitudinal tread members as shown in Figure 3, the tread members 50 are of double sheet thickness with the sheet being bent downwardly so that the bend of the sheet is in the top plane of the finished grating and the tread members 51 are of double sheet thickness with the sheet being bent upwardly so that the bend of the sheet is in the bottom plane of the finshed grating. The panels 47 and 49 are bent at the same time into a vertical position flat against the adjacent side i of the tread members 50 and 51 to. which they are at 'tached'with the web members 48 joining the adjacent tread members as shown'in Figure 3.

After the sheet 40 has been bent and takes up the form shown in Figure 3 the tread members 5 1 are, pulled length- Wisein the direction of thegratinginthe direction or the arrowA to bring the web members 48 into aposition at right angles to the tread members '50 and .51 asshown in Figure 4.

"The open ends of the grating between thetread mem- 'hers "50and 51 are closed by bending "inwardsat right anglesthe end ,portion 52.01 the outertread 50 and the end portions 53 of the inner treads, 50 and 51 and welding the ends .of these end portions "52 .and .53 to .the outerends of the adjacent treads "50 and "51. Theends T52 and 53 Whenanchored to thetreads 5.0 and gslihold the grating against displacement iniits 'horizontalplane with the web members 48 holding the double sheet sides of the treadmembers '50 andJSI'fromgaping open.

.Alternatebending'lines are provided with a-series of :aperturesl54 which, when the sheet '40'isxbent along these t-dlternate'lines to form the double sheet'thickness tread members .50 and 51 the apertures 54 "formserrations on the top of-the trends which serrations may he required 'fforz many types ofgrating applications.

:Normally the structure as above described .requires no'.further means of "holding the various abutting faces of'the sheet together as any distortion'tending to separate the abutting faces would'have to cause distortion of the .web members 48. Eachweb member-48 is joined vertical- Ily to .the end members 47 and 49 which in turn are joined horizontally to the tread members 50 andSl along one edge, theilatter horizontal; joints alternating'between thetopiand thebottomtplane of the gratingat each of the web members .48. '1 he strength of the web members and the-tread members is a function of the sheet thick- :ness andthe designeddepth of the grating with respect .to.,the.load normally expected to'be applied to the grating "soathatsno. gaping of the'abutting 'faces of the sheet forming the tread members should beexpected and therefore no distortion offthe web members. However, should additional securingmeans .be required, these can be efiected "by .spotwelding the edges of the abutting faces of the sheet forming the tread member at the location of the web members.

Gratings fabricated in the "form above described have "equivalent strength both laterally and longitudinally and canbe made ,in .any depth to carry .maximumlloading. Ihe vertical openings in the gratings can .be made any size to suit working conditions and .the .clean lines of theopenings will prevent bridgingby snow or ice particularly nder slush conditions and,.should"bridging occur, this can be quickly cleared as there are no projecting surfaces within-the openings to hold the"bridging ma- :terial. The tread surfaces which are the result of'tolded ,over metal presenting alternatively rounded surfaces and two separate metal-edges brought together, but all being in the same horizontal plane, provide a smooth tread surfacefor the grating which is not detracted from by the :serrationsof the treadsurface provided for, greater loot- .ingsafety.

'What'l claim is:

"1. In a grating for use on running boards or thelike formed from a single sheet of metal slitfand bent alternatively upwardly and downwardly relative .to the plane of the sheet to'form a series-oivertically disposed longitudinal tread members, the saidlongitudinal tread members being formed of double sheet thickness with thebend of the sheet of alternate tread members being disposed 'on the'top horizontal plane of the gratingand the bend or the sheet on intervening tread members being disposed on the bottom horizontalgplane of'theygratin'g, and webrnem'bers joiningsaid longitudinal tread members 'atqspaced intervals lengthwise of the grating, the said web :members -havingtwo end portions formed from the :sheetiextended from the adjacent longitudinal 'treadmembars and bent into a vertical plane against said longitudinal tread members, one end portion of each wb member being ofiset relative to the other lengthwise of the longitudinal tread members and a joining portion connecting the adjacent vertical edges of the said end portions of the web members, the said joining portions of the web members being disposed at right angles to said longitudinal tread members with-the end portions joining alternate longitudinal :tread members being :bent downwardly relative to the top horizontal plane of the grating while'the endportionsjoining intervening 'lon'gitudinal tread rnembersbeingbent upwards relative to thebottorn horizontal plane of the grating, the said joiriingportions of the web. membersf holding .the -.?double sheet sides of said longitudinal tread members and the end portions of the web members in close abutment with each other and in spaced parallel relation to adjacent longitudinal treadmernbers, .the .said. longitudinal treadcmembersrhaving their .end portions bent at .rig'htangles and secured to the ends of adjacent longitudinal tread .members..to close the ends ofthe grating.andIhdldisaidigratingfinzlits :formed position. i

2. .In t a grating for. use on ,run 'ng'boards .or :the 'like formed from a single sheet of metal -slitand bent alternatively upwardly and downwardly relative to the .planeidf the .sheet to form a series of vertically disposed longitudinal tread members, .a series .of' horizontally extending spaced lines of slits,-each of .the slits in eachl'lineZ-ineluding parallel longitudinally extending end portions ofiset from each other in the longitudinal"directionof the grating and an intermediate transversely extending portion extending between and interconnecting adjacent ends of said longitudinally extending endportions o'fvthe slits, the parallel end .portions of theislits overlapping .the end portions of .the adjacent .slitsin thessame longitudinal line, .the superposed .slits .in the .next adjacent horizontal line of slits'beingotfset in :a reverse direction from thesuperposed slits inadjacent' lines, the said longitudinal tread members being'formed of double sheet'thickness with the bend of the sheet of alternate'treadmembers being disposed on the top horizontal plane of.the

grating and the .bend of the sheet on intervening'tread members being disposed on the bottom horizontal plane ofthe grating, and web members-joining said'longitudinal tread.members.atspacedintervals lengthwise of the ,grating, said web' members being formed from that portion of the sheet between the overlapping slits in the same longitudinal lineand having two endportions'tormedlfrom the sheet extended from the adjacentlongitudinaltread members and bent into avertical p'lane against saidlong'itudinal tread members, one end portion of each web member'being o'ttsetrelative to the other lengthwise of the' longitudinal tread members and a joining portion connecting the adjacent vertical edges of the said .end portions of the web-members, the said joining portions of the web members being disposed at right angles to said longitudinal tread memberswith the end portionsfjoining alternate longitudinal tread members being'bent downwardly relative tothe top horizontal plane of thegrating while the end portions joining intervening longitudinal tread members being bent upwards relative to .the bottom horizontal plane of the grating, the said joining portions of the web membersholding the double sheet sides ."df saidlongitudinal .treatLmemb'ers and [the end portions of the web members in close-abutment with eachzotherand in spaced parallel .relation to .adjacentilong'itudinal tread members, the said longitudinal tread members (having their endportions'bent at right angles 'andsecured to the ends of adjacent longitudinal members to close "the ends of thegrating and hold said grating in its formed position. "1

3. In a grating for use'on nnnningboardsorthe like formed from 'a singlesheet 'of metal slit and bentalternatively' npwardly and downwardly relative to i the planet-of thefshegt" to form a series rdf vertically V disposed ilongi' rm-hat.

tudinal tread members, the said longitudinal tread members being formed of double sheet thickness with the bend of the sheet of alternate tread members being disposed on the top horizontal plane of the grating and the bend of the sheet on intervening tread members being disposed on the bottom horizontal plane of the grating, a series of apertures disposed along the lines forming the top edges of the longitudinal tread members, the said apertures forming a rough serrated tread surface to said tread members, and web members joining said longitudinal tread members at spaced intervals lengthwise of the grating, the said web members having two end portions formed from the sheet extended from the adjacent longitudinal tread members and bent into a vertical plane against said longitudinal tread members, one end portion of each Web member being offset relative to the other lengthwise of the longitudinal tread members and a joining portion connecting the adjacent vertical edges of the said end portions of the Web members, the said joining portions of the web members being disposed at right angles to said longitudinal tread members with the end portions joining alternate longitudinal tread members being bent downwardly relative to the top horizontal plane of the grating while the end portions joining intervening longitudinal tread members being bent upwards relative to the bottom horizontal plane of the grating, the said joining portions of the web members holding the double sheet sides of said longitudinal tread members and the end portions of the Web members in close abutment with each other and in spaced parallel relation to adjacent longitudinal tread members, the said longitudinal tread members having their end portions bent at right angles and secured to the end of adjacent longitudinal tread members to close the end of the grating and hold said grating in its formed position.

References Cited in the file of this patent UNITED STATES PATENTS 312,864 Kinney Feb. 24, 1885' 683,642 Fairbairn Oct. 1, 1901 854,927 Clark May 28, 1907 1,389,294 Dean Aug. 30, 1921 1,953,657 Pierce Apr. 3, 1934 2,191,788 Collins Feb. 27, 1940 2,208,020 Delanty July 16, 1940 2,652,133 Leigh Sept. 15, 1953 FOREIGN PATENTS 483,814 Canada June 3, 1952 

